Wednesday, July 13, 2016

Intestinal Intussusception in the Cat

Intestinal Intussusception in the Cat

This big medical term
describes an intestinal condition that, if not recognized and treated promptly
with surgery, could have dire consequences for your cat.

A few
months ago, a client brought her 4 month-old female kitten, Squeegee, to my
feline-only veterinary hospital for an exam.
The kitten had been doing great, eating well, growing nicely, and
playing like a maniac, until two days before when she began to vomit. She became lethargic, the vomiting
progressed, and her appetite abruptly disappeared.

My physical
examination revealed a markedly subdued, dehydrated little orange tabby. Her body temperature was normal, and she was
an appropriate weight for her age. The
exam was fairly unremarkable, until I got to the abdomen. As I gently pressed on her belly with my
fingers, I could feel a tubular, sausage-like structure. She squirmed and tried to get away. I gave her a little break, and then I softly
pressed again to be sure of my findings.
It was unmistakable; there was something seriously amiss in Squeegee’s
belly. She was too young for cancer or
inflammatory bowel disease. A discreetly
thickened loop of bowel in a kitten was highly suspicious for a condition
called intestinal intussusception. I
recommended abdominal ultrasound to corroborate the diagnosis, and the owner
agreed. My suspicions were quickly
confirmed, and preparations for immediate surgery were begun.

intussusceptum (“inta-suh-SEP-tum). The outer portion that receives
the piece of intestine is called the intussuscipiens
(“inta-suh-SIP-ee-enz”). (When studying this in veterinary school, my trick for
distinguishing between the two parts was to remember that the intussuscipiens is the recipient.) Intussusceptions are named by first citing the
intussusceptum, and then citing the intussuscipiens. For example, a “gastroesophageal”
intussusception is one where a piece of the stomach (“gastro”) pushes itself
into the esophagus. An “enterocolic”
intussusception is one in which a portion of the small intestine (“entero”)
pushes into the colon. In cats, the most
common type is intestinal, where both the intussusceptum (the piece that
pushes) and the intusscipiens (the piece that receives) are portions of small
intestine.

Warning: big words ahead. An intussusception (pronounced
“inta-suh-SEP-shun”) is a condition in which a piece of intestine telescopes or
invaginates into another piece of intestine.
(See drawing.) The piece of
intestine that pushes into the other piece is called the

Intussusceptions
have been well-described in dogs. They
are most common in young dogs, with German Shepherds being the most commonly
reported breed, although whether there is a true breed predisposition is
debatable. Less information is
available regarding intussusceptions in cats.
In 1994, a series consisting of 12 cases was reported in cats. Similar to dogs, the majority occurred in
cats that were under 1 year of age. Most
cases involved the domestic shorthaired breed, although Siamese and Burmese
cats were overrepresented, suggesting that these breeds might be more
susceptible. This was a small study. A
few years ago (2009), a larger case series was published (20 cats) that shed
additional light on the subject.

In the more
recent study, there was a bi-modal age distribution: 10 of the 20 cats were under a year of age
when the intussusception occurred.
Interestingly, nine of the cats were older than 6 years of age. (The remaining cat was 2 years old.) The most
common clinical signs reported were the same signs that I saw in little
Squeegee: poor appetite, lethargy, and
vomiting. Weight loss and diarrhea were
also commonly reported. Most (13) of the
cats examined had some degree of dehydration.
Nearly all of the cats had some abdominal abnormality that could be
discerned during the physical exam, including abdominal pain, an abdominal
mass, or a discreetly thickened segment of intestine.

Once
there’s a suspicion of intussusception, a diagnosis needs to be confirmed. X-rays usually reveal some abnormality of the
intestinal tract, however, a definitive diagnosis cannot usually be made on
x-rays alone. Ultrasound is a better
test for making the diagnosis. In the
study from 2009, seven cats underwent abdominal ultrasound, and in all seven
cats, a definite diagnosis was made based on the ultrasound findings. It was ultrasound that confirmed the
diagnosis in Squeegee as well.

Intussusception
is a surgical disease. Without surgery,
cats will invariably succumb to the disorder.
Once the cat is taken to surgery, an attempt is made to “reduce” the
intussusception, i.e. separate the intussusceptum from the
intussuscipiens. While it might seem
intuitive to do this by applying traction on the intussusceptum and pulling it
out from the intussuscipiens, the proper technique actually involves grasping
the intussuscipiens and gently “milking” the intussusceptum from within the
intussuscipiens, carefully pushing it out.
In some cases, however adhesions have formed between the two pieces, and
they cannot be separated from each other.
In these cases, the entire intussusception needs to be surgically cut
from the intestine, and the two normal ends of the intestine reattached to each
other.

Recurrence
of intussusception after surgery has been reported in dogs. Interestingly, in dogs and people, if
recurrence occurs, it is usually in an anatomic location other than the
original site. In an attempt to reduce
recurrence, a surgeon may elect to perform a procedure at surgery called
“enteroplication”. This technique
creates permanent attachments between adjacent loops of intestine. Although this procedure is said to reduce
the incidence of recurrence, it sometimes leads to complications. Thus,
the decision whether or not to perform enteroplication is at the discretion of
the individual surgeon. Recurrence of
intussusception appears to be less of a problem in cats, although data to
confirm the actual incidence are lacking.
In the study from 2009, 13 cats underwent surgery. One cat was euthanized at the time of
surgery. Three of the 12 cats that
underwent surgery had enteroplication performed. Two of those three cats experienced
significant complications from the enteroplication; one cat died and one had to
be euthanized. The other 10 cats were
discharged from the hospital. Five of
them were lost to follow-up, but the other five did well and never experienced
a recurrence of intussusception. Owing
to the small number of cats in the 2009 study that underwent enteroplication,
we aren’t able to draw any conclusions as to whether this technique is
beneficial or not in preventing recurrence, compared to the potential risks.

Squeegee’s
intussusception was easily reduced at the time of surgery, and enteroplication
was not performed. She was spayed at the
same time. I spoke to her owner a few
days ago, as they were preparing to celebrate her first birthday. She is doing well and she weighs
approximately twice as much as when she came in to my
hospital feeling sick. Because
recurrence is a possibility, we will always remain on our guard, but for now it
seems that she’s made a total recovery.

Dr. Arnold Plotnick (MS, DVM, ACVIM) blogs about professional and personal life experiences as an expert in the field of feline veterinary medicine.

Dr. Arnold Plotnick is a board-certified veterinary internist, feline expert, and the founder of Manhattan Cat Specialists. In addition to his medical work, he is an award-winning veterinary medicine writer.